000007800 001__ 7800
000007800 005__ 20260113123823.0
000007800 037__ $$aSCART-2026-0053
000007800 100__ $$aSarkar, Mrinmoy
000007800 245__ $$aAsteroseismic modelling of mild Am δ Sct stars: HD 13038 and HD 13079
000007800 260__ $$c2026
000007800 520__ $$aIn this paper, we present an asteroseismic analysis of two mild Am δ Scuti (δ Sct) pulsators, HD 13038 and HD 13079, utilising both the space and ground-based photometry. From multi-sector TESS observations with different cadences, 37 pulsation frequencies for HD 13038 and 69 for HD 13079 were extracted with SNR > 5. Notably, light curves of HD 13079 are affected by ∼ 12.3% of the flux from its neighbourhood star HD 13079B situated at an angular separation of 6.48 ± 2.70 arcsec. For HD 13038, the large frequency separation is 6.08 d^{-1} exhibiting two vertical ridges of radial modes consistent with the frequency ratios and pulsation constants (Q-value). However, the seismic age indicates the left-ridge frequencies are more acceptable as radial modes with orders n = 5, 7. We found that one radial ridge is visible for HD 13079 at a large separation of 5.15 d^{-1} with orders n = 1, 2, 3, 4, 6. For both stars, excited radial overtones are higher than the predicted values for these T_{eff} range. The stellar parameters were calculated using a mass-metallicity grid followed by seismic-chi² minimisation technique constraining identified radial modes. In the frequency spectrum of HD 13038, the spotted rotation frequency at f_{rot} ≈ 0.94 d^{-1} provides an inclination angle ≈ 90 degrees. The frequency spectrum of combined TESS light curve for HD 13079, reveals f_{rot} ≈ 0.86 d^{-1} is in close agreement to the observed mean quintuplet splitting frequency ≈ 0.77 d^{-1}, provides an inclination angle of 42 ± 4◦. The present study is a crucial step in comprehending the processes that underlie the excitation of high-order radial modes in Am stars.
000007800 594__ $$aNO
000007800 6531_ $$aAsteroseismology
000007800 6531_ $$aAm Star
000007800 6531_ $$aδ Sct pulsations
000007800 6531_ $$aIndividual: HD 13038
000007800 6531_ $$aIndividual: HD 13079
000007800 6531_ $$aStellar Rotation
000007800 6531_ $$aQuintuplets
000007800 700__ $$aJoshi, Santosh
000007800 700__ $$aDupret, Marc-Antoine
000007800 700__ $$aBuldgen, Gaël
000007800 700__ $$aDileep, Athul
000007800 700__ $$aDe Cat, Peter
000007800 700__ $$aGhosh, Surath C.
000007800 700__ $$aGupta, Archana
000007800 773__ $$pMonthly Notices of the Royal Astronomical Society$$y2026
000007800 8560_ $$fpeter.decat@ksb-orb.be
000007800 905__ $$asubmitted to
000007800 980__ $$aREFERD